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From:   Jason Wang <jasowang@redhat.com>
Date:   Wed, 22 Jun 2022 09:17:37 +0800
Message-ID: <CACGkMEsg9791gQAtsz6fCM_=9_VmbqY=FehoTnpyiaJ7mCosDA@mail.gmail.com>
Subject: Re: [PATCH V2] virtio: disable notification hardening by default
To:     Cornelia Huck <cohuck@redhat.com>
Cc:     Halil Pasic <pasic@linux.ibm.com>, mst <mst@redhat.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        linux-s390@vger.kernel.org,
        virtualization <virtualization@lists.linux-foundation.org>,
        kvm <kvm@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
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On Tue, Jun 21, 2022 at 5:58 PM Cornelia Huck <cohuck@redhat.com> wrote:
>
> On Tue, Jun 21 2022, Jason Wang <jasowang@redhat.com> wrote:
>
> > On Tue, Jun 21, 2022 at 5:16 PM Cornelia Huck <cohuck@redhat.com> wrote:
> >>
> >> The ifdeffery looks a big ugly, but I don't have a better idea.
> >
> > I guess you meant the ccw part, I leave the spinlock here in V1, but
> > Michael prefers to have that.
>
> Not doing the locking dance is good; I think the #ifdefs all over are a
> bit ugly, but as I said, I can't think of a good, less-ugly way...

Probably, but this is the way that is used by other subsystems. E.g
CONFIG_HARDEN_USERCOPY etc.

>
> > In the future, we may consider removing that, one possible way is to
> > have a per driver boolean for the hardening.
>
> As in "we've reviewed and tested this driver, so let's turn it on for
> every device bound to it"?

Right.

Thanks

>